What are the system limits of the OPC UA Server with S7-1500 with firmware V2.0.x and V2.1.x?
|1510, 1511, 1512, 1513||1515, 1516, 1505S||1517, 1518, 1507S|
|Maximum number of subscriptions with more than 1000 monitored elements per subscription over all sessions||10||10|
Maximum number of subscriptions with a maximum of 1000 monitored elements per subscription over all sessions
|Maximum number of subscriptions per session||20||20||20|
|Possible sampling intervals||100ms, 250ms, 500ms, 1000ms, 2500ms, 5000ms||100ms, 250ms, 500ms, 1000ms, 2500ms, 5000ms||50ms, 100ms, 250ms, 500ms, 1000ms, 2500ms, 5000ms|
|Smallest possible Send interval||500ms||200ms||50ms|
|Maximum number of sessions||32||48||64|
- The number of 10,000 elements per subscription is always the maximum.
- A subscription with a maximum of 1000 elements cannot be converted into a subscription with more than 1000 elements.
- With regard to performance, it does not matter over how many subscriptions the number of elements is distributed.
- Variant A: Large number of subscriptions with small number of elements.
- Variant B: Small number of subscriptions and large number of elements.
- The difference is the larger main memory requirement in Variant A.
- If more elements are specified in the table above than registered in a subscription, the status code "BadTooManyMonitoredItems" is returned in the OPC UA client. In this case the client should attempt to register the remaining elements via another subscription.
- If the maximum quantity framework of the server is exceeded, the status message "BadOutOfMemory" is sent to the OPC UA client.
- Independent of the system limits mentioned above it is recommended not to exceed the number of elements to be monitored specified in Table 2 as overall quantity framework of the server.
1510, 1511, 1511C,
|1515, 1516||1517, 1518, 1507S|
|* Recommended maximum number of elements over all subscriptions||1000||2000||10000|
* These recommendations are based on a user program with the following conditions:
- Only OPC UA communication (no other communication, like TCP, for example, is executed).
- 1 second sampling and Send interval.
- No OBs with priority greater than 15 (this means no interruption of the communication through OB processing).
50% maximum communication load
Data type of the elements: WSTRING
Note on the versions V2.5 and higher
The system limits described above no longer apply to firmware V2.5 and higher.
More information is available in the following entries:
- Which restrictions do you have to consider with the OPC UA Server of S7-1500 CPU with the firmware V2.0.x or V2.1.x in compatibility mode of firmware V2.5?
- What are the possible causes and remedies for appearance of the status code in the OPC UA client when using subscriptions?